1. Field of the Invention
The present invention relates to a control device, an image forming apparatus, and a control method.
2. Description of the Related Art
In image forming apparatuses such as a multifunction printer (MFP) and a laser printer (LP), the supply of power to respective loads, which are units included in the image forming apparatus, is controlled to thereby control driving of the respective units. Among such image forming apparatuses, there is an image forming apparatus in which when a power saving mode in which power consumption is suppressed is set, the supply of power to a main central processing unit (CPU) which controls the entire image forming apparatus is stopped in order to suppress power consumption while the power is supplied only to a unit for detecting a specific factor (referred to as a return factor) that the image forming apparatus uses to return a different operation mode from the power saving mode. Then, when the return factor is detected, the image forming apparatus returns to a normal mode from the power saving mode so that the supply of power to the respective units is initiated. However, in many cases, image forming apparatuses are under a network environment in which the image forming apparatuses are connected to a network. Among such image forming apparatuses, there is an image forming apparatus which includes a sub-CPU that consumes less power than a main CPU. In that image forming apparatus, the sub-CPU performs response actions under the network environment in place of the main CPU even when a power saving mode is set, and when the supply of power to the main CPU is stopped. In recent years, techniques have been developed which decrease unnecessary power consumption in regard to response actions under the network environment when an operation mode of an image forming apparatus located under a network environment is set to a power saving mode (for example, see Japanese Patent No. 4440326).
However, in the technique disclosed in Japanese Patent No. 4440326, when an operation mode of an image forming apparatus which is in a stand-alone state in which the image forming apparatus is not connected to a network is set to a power saving mode, power is supplied to a unit that performs response actions even if the unit does not need to perform response actions which are necessary under the network environment. As a result, power is consumed unnecessarily.
There is a need to reduce power consumption of an image forming apparatus more effectively.